Detection of cystic fibrosis protein by isoelectric focusing of serum [letter].

Several cystic fibrosis research groups have independently attempted to reproduce the isoelectric 
focusing work of Wilson et al. The protocol that we employed 
with the LKB Mulitphor electrofocusing apparatus was that of Wilson et 
al., although fixing and staining of the polyacrylamide gels was performed 
in a boiling water bath for 30 min. In 10 of 
11 sera from patients with CF, the cystic fibrosis protein band 
was directly identified by each of two independent observers and in 
the sera from nine obligate heterozygote individuals, the CFP band was 
noted in seven and eight instances by each observer, respectively. In 
sera from 26 normal control individuals, the CFP band was observed 
in two instances. Our results would support the view that the 
CFP band is indeed directly identifiable in both CT heterozygote and 
homozygote sera without recourse to photographic image enhancement and that its 
frequency of occurrence is similar to that reported previously. 